KR20130103326A - Hybrid construction machinery - Google Patents

Abstract

In a hybrid construction machine using an electric motor for driving a swinging structure, a hybrid construction machine capable of satisfactory work can be provided even when a situation arises in which a torque of the electric motor cannot be generated for any reason. As a driving device for the swinging structure, both a hydraulic motor 27 and an electric motor 25 are provided, and a controller 80 for switching between the hydraulic swinging motor and the electric swinging hybrid mode and the hydraulic motor swinging mode is provided. . At this time, sufficient operability and performance are realized in both modes. Usually, energy saving operation is performed in the hydraulic-electric combined swing mode. When the power storage amount is out of a predetermined range, or when an inverter failure or other electric system abnormality occurs, the operation is switched to the hydraulic single turning mode, and the hydraulic motor alone allows driving with normal braking torque.

Description

Hybrid Construction Machinery {HYBRID 기계 CONSTRUCTION MACHINERY}

TECHNICAL FIELD This invention relates to a hybrid construction machine. Specifically, It is related with the hybrid construction machine which has turning bodies, such as a hydraulic excavator.

For example, in a construction machine such as a hydraulic excavator, a fuel such as gasoline or diesel is used as a power source, and the hydraulic pump is driven by an engine to generate a hydraulic pressure, thereby driving a hydraulic motor such as a hydraulic motor or a hydraulic cylinder. Hydraulic actuators are widely used as actuators for construction machinery because of their small size, light weight, and large output.

On the other hand, in recent years, by using an electric motor and a power storage device (battery, electric double layer capacitor, etc.), the construction machine which improved energy efficiency compared to the conventional construction machine using only a hydraulic actuator, and aimed at energy saving is proposed (patent document). One).

Electric motors (electric actuators) are more energy efficient than hydraulic actuators and have an energy-efficient feature that can regenerate kinetic energy during braking as electrical energy (in the case of hydraulic actuators, release them as heat).

For example, in the prior art disclosed in Patent Literature 1, an embodiment of a hydraulic excavator equipped with an electric motor as a drive actuator of a swinging body is presented. An actuator (normally using a hydraulic motor) that drives the upper swing structure of the hydraulic excavator with respect to the lower traveling body has a high frequency of use, and frequently starts, stops, and accelerates and decelerates in operation.

At this time, the kinetic energy of the swinging body at the time of deceleration (braking) is dissipated as heat on the hydraulic circuit in the case of the hydraulic actuator, but in the case of the electric motor, regeneration as electric energy can be expected, and energy saving can be achieved. do.

Moreover, the construction machine which mounts both a hydraulic motor and an electric motor, and drives a turning body by total torque is proposed and disclosed (patent document 2 and patent document 3).

In Patent Document 2, an energy regeneration device for a hydraulic construction machine is disclosed in which an electric motor is directly connected to a swing-drive hydraulic motor, and the controller commands an output torque to the electric motor by the amount of operation of the operation lever. At the time of deceleration (braking), the electric motor regenerates the kinetic energy of the swinging structure and stores it in the battery as electrical energy.

In Patent Document 3, the torque command value to the electric motor is calculated using the differential pressures on the in side and the out side of the swing drive hydraulic motor, and the output torque distribution between the hydraulic motor and the electric motor is calculated. A hybrid construction machine to be performed is disclosed.

In the prior arts of Patent Documents 2 and 3, both the electric motor and the hydraulic motor are used together as the turning drive actuator, so that even the operator who has become accustomed to the construction machine of the conventional hydraulic actuator drive can operate without discomfort and is simple. Moreover, the energy saving is aimed at the structure which is easy to use.

Japanese Patent No. 3647319 Japanese Patent No. 4024120 Japanese Patent Application Publication No. 2008-63888

In the hybrid hydraulic excavator described in Patent Literature 1, since the kinetic energy of the swinging body at the time of deceleration (braking) is regenerated as electric energy by the electric motor, it is effective from the viewpoint of energy saving.

However, since an electric motor has a characteristic different from a hydraulic motor, when an electric motor is used for the drive of the turning body of a construction machine, the following problems arise.

(1) Hunting due to poor speed feedback control of the electric motor (especially low speed region, stationary state).

(2) Operational discomfort due to the difference in characteristics from the hydraulic motor.

(3) Overheating of a motor or an inverter in the work which continuously outputs a torque (for example, pushing work) in the state which a motor does not rotate.

(4) The use of an electric motor that guarantees output equivalent to a hydraulic motor results in an excessively large appearance or a significant increase in cost.

In the hybrid hydraulic excavators described in Patent Literatures 2 and 3, both the hydraulic motor and the electric motor are mounted, and the above-mentioned problems are solved by driving the swinging body by the total torque, thereby accustoming to the construction machinery of the conventional hydraulic actuator drive. The operator can operate without discomfort and at the same time save energy with a simple and practical configuration.

However, in any of the prior arts described in Patent Documents 1 to 3 described above, the electric motor is responsible for a constant torque among all the torques required for the turning drive. If the torque of the electric motor cannot be generated for some reason such as energy shortage of the device or an overcharged state, there is a problem that the total torque for driving the swinging body is insufficient, so that starting and stopping cannot be performed as in normal operation.

For example, when a sudden abnormality occurs in a state where the speed of the swinging body is high and the kinetic energy is large, the electric motor is in a free-run state, and the prior art of Patent Document 1 cannot stop, and Patent Documents 2 and 3 In the prior art, the stopping distance and the stopping time are longer than the normal state, which is a serious problem for safety.

In addition, immediately after the machine starts, there is a possibility that the amount of energy of the power storage device may decrease due to natural discharge or the like during machine stoppage or storage. In this case, since the turning electric motor is incapable of outputting, the turning operation cannot be started immediately. First, since it is necessary to charge until the power storage amount of a power storage device reaches a predetermined value, even if an operator wants to start work, it is necessary to wait until completion of charging.

SUMMARY OF THE INVENTION An object of the present invention is a hybrid construction machine in which a hybrid construction machine using an electric motor for driving a swinging body can perform satisfactory work even when a situation in which torque of the electric motor cannot be generated for any reason occurs. To provide.

The hybrid construction machine of the present invention includes a hydraulic motor and an electric motor for driving a swinging structure, and a hydraulic-electric hybrid swinging mode for driving the swinging body by driving both the hydraulic motor and the electric motor by a control device. And switching to the hydraulic single swing mode for driving only the hydraulic motor to drive the swing structure. In switching between the hydraulic-electric combined swing mode and the hydraulic single swing mode, sufficient operability and performance are realized in both modes. Usually, energy saving operation is performed in the hydraulic-electric combined swing mode. When the power storage amount is out of a predetermined range, or when an inverter failure or other electric system abnormality occurs, the motor is switched to the hydraulic single swing mode and driven at the normal braking torque by the hydraulic motor alone even when the electric motor is in the free run state. Make it possible.

According to the present invention, for driving a swinging structure, both a hydraulic motor and an electric motor are provided, and a swing driving mode (hydraulic electric hybrid swing mode) is performed by torque of both the hydraulic motor and the electric motor, and the hydraulic motor turns alone. By setting it as the structure which can be switched to the driving mode (hydraulic single swing mode), in a hydraulic-electric combined swing mode, for example, the operation | movement peculiar to hydraulic actuators, such as pressure excavation, and the operation feeling peculiar to a hydraulic actuator are realized, In braking (deceleration), energy saving can be realized by regenerating the kinetic energy of the swinging structure by the electric motor. When the energy remaining amount of the power storage device for storing the regenerated electric energy is insufficient, in the case of overcharging, or when a failure, abnormality or warning occurs in the electric system, the hydraulic pressure is switched to the hydraulic single turning mode. The motor alone can be used to drive normal turning torque, and the operation can be continued. In addition, at start-up, even if the energy remaining amount of the power storage device is insufficient, the work can be started immediately.

Thus, according to this invention, even if the situation which the torque of an electric motor cannot generate | occur | produce for some reason arises, satisfactory operation | work can be performed.

1 is a side view of a hybrid hydraulic excavator according to a first embodiment of the present invention.
It is a system block diagram of the main electric and hydraulic equipment of the hybrid hydraulic excavator which concerns on 1st Embodiment of this invention.
3 is a system configuration and control block diagram of the hybrid hydraulic excavator according to the first embodiment of the present invention.
It is a figure which shows the structure of the turning hydraulic system in 1st Embodiment of this invention.
It is a figure which shows the torque control characteristic of the hydraulic pump in 1st Embodiment of this invention.
It is a figure which shows the meter in opening area characteristic and the bleed-off opening area characteristic of the turning spool in 1st Embodiment of this invention.
It is a figure which shows the meter out opening area characteristic of the turning spool in 1st Embodiment of this invention.
FIG. 7 shows the composite aperture area characteristics of the meter-in aperture of the swinging spool 61 and the center bypass cut valve 63 with respect to the hydraulic pilot signal (operation pilot pressure) in the first embodiment of the present invention. Drawing.
Fig. 8 is a hydraulic pilot signal (pilot pressure), meter in pressure (M / I pressure), assist torque of a swing electric motor, in swing driving in a hydraulic-electric hybrid swing mode in the first embodiment of the present invention. It is a figure which shows the time-series waveform of the rotation speed (rotation speed) of an upper swing body.
FIG. 9: is a figure which shows the meter out opening area characteristic of the turning spool 61 with respect to the hydraulic pilot signal (operation pilot pressure) in 1st Embodiment of this invention.
Fig. 10 is an assist of hydraulic pilot signal (pilot pressure), meter out pressure (M / O pressure), swing electric motor at the time of swing braking stop in the hydraulic-electric hybrid swing mode in the first embodiment of the present invention. It is a figure which shows the time-series waveform of torque and the rotation speed (rotation speed) of an upper swing body.
It is a figure which shows the relief pressure characteristic of the variable overload relief valve for turning in 1st Embodiment of this invention.
It is a figure which shows in flowchart with the abnormality processing sequence (switching from hydraulic-electric combined swing mode to hydraulic single swing mode) of the hybrid hydraulic excavator by 1st Embodiment of this invention.
It is a figure which shows in flowchart with the abnormality process sequence (return to hydraulic-electric hybrid swing mode) of the hybrid hydraulic excavator by 1st Embodiment of this invention.
It is a figure which shows the flowchart of the starting sequence of a normal hydraulic excavator.
FIG. 15 is a flowchart showing a startup sequence of a conventional hybrid hydraulic excavator having a capacitor and a turning electric motor. FIG.
It is a figure which shows the flowchart of the starting sequence of the hybrid hydraulic excavator which concerns on 1st Embodiment of this invention.
It is a system block diagram of the main electric and hydraulic equipment of the hybrid hydraulic excavator which concerns on 2nd Embodiment of this invention.
It is a system block diagram of the main electric and hydraulic equipment of the hybrid hydraulic excavator which concerns on 3rd Embodiment of this invention.
It is a system block diagram of the main electric and hydraulic equipment of the hybrid hydraulic excavator which concerns on 4th Embodiment of this invention.
It is a system block diagram of the main electric and hydraulic equipment of the hybrid hydraulic excavator which concerns on 5th Embodiment of this invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described using a hydraulic excavator as an example of a construction machine. Moreover, since this invention is applicable to the whole construction machine (including a working machine) provided with a turning body, application of this invention is not limited to a hydraulic excavator. For example, the present invention is applicable to other construction machinery such as a crane car provided with a swinging structure.

The side view of the hybrid hydraulic excavator which concerns on 1st Embodiment of this invention is shown in FIG.

In FIG. 1, the hybrid hydraulic excavator is provided with a lower traveling body 10, an upper swinging body 20, and a shovel mechanism 30.

The lower traveling body 10 is a pair which independently drive-controls a pair of crawlers 11a and 11b, crawler frames 12a and 12b (only one is shown in FIG. 1), and each crawler 11a and 11b. Of the hydraulic motors 13 and 14 for driving and the deceleration mechanism thereof.

The upper revolving structure 20 includes a revolving frame 21, an engine 22 serving as a prime mover provided on the revolving frame 21, and an assist generating motor 23 (charger) driven by the engine 22. And the electric double layer capacitor 24 connected to the turning electric motor 25 and the turning hydraulic motor 27, the assist power generation motor 23, and the turning electric motor 25, and the turning electric motor 25. ) And a deceleration mechanism 26 for decelerating rotation of the turning hydraulic motor 27, and the driving force of the turning electric motor 25 and the turning hydraulic motor 27 is transmitted through the reduction mechanism 26. By the driving force, the upper swinging structure 20 (swinging frame 21) is pivotally driven with respect to the lower traveling body 10.

In addition, a shovel mechanism (front device) 30 is mounted on the upper swing structure 20. The shovel mechanism 30 includes a boom 31, a boom cylinder 32 for driving the boom 31, an arm 33 rotatably supported near the tip of the boom 31, and an arm ( An arm cylinder 34 for driving 33, a bucket 35 rotatably supported at the tip of the arm 33, a bucket cylinder 36 for driving the bucket 35, and the like. .

In addition, on the turning frame 21 of the upper swinging body 20, the above-described traveling hydraulic motors 13 and 14, the swinging hydraulic motor 27, the boom cylinder 32, the arc cylinder 34, the bucket cylinder A hydraulic system 40 for driving a hydraulic actuator such as 36 is mounted. The hydraulic system 40 includes a hydraulic pump 41 (FIG. 2) serving as a hydraulic source for generating hydraulic pressure and a control valve 42 (FIG. 2) for driving control of each actuator, and the hydraulic pump 41 Is driven by the engine 22.

The system structure of the main electric and hydraulic equipment of a hydraulic excavator is shown in FIG. As shown in FIG. 2, the driving force of the engine 22 is transmitted to the hydraulic pump 41. The control valve 42 adjusts the flow rate and direction of the pressure oil supplied to the turning hydraulic motor 27 according to the turning operation command (hydraulic pilot signal) from the turning lever device 72 (refer FIG. 3) for turning. To control. Moreover, the control valve 42 responds to the operation command (hydraulic pilot signal) from the operation lever device 73 (refer FIG. 3) other than turning, and the boom cylinder 32, the arm cylinder 34, and the bucket cylinder 36 And the flow rate and direction of the hydraulic oil supplied to the traveling hydraulic motors 13 and 14.

The electric system is composed of the assist electric power generation motor 23, the capacitor 24, the electric motor 25 for turning, the power control unit 55, the main contactor 56, and the like. The power control unit 55 has a chopper 51, inverters 52 and 53, a smoothing capacitor 54, and the like, and the main contactor 56 has a main relay 57, an inrush current preventing circuit 58, and the like. have.

DC power from the capacitor 24 is boosted by a chopper 51 to a predetermined bus voltage, and an inverter 52 for driving the turning electric motor 25 and an inverter for driving the assist power generation motor 23 ( 53). The smoothing capacitor 54 is provided in order to stabilize a bus voltage. The rotating shaft of the turning electric motor 25 and the turning hydraulic motor 27 is coupled, and drives the upper turning body 20 via the reduction mechanism 26. As shown in FIG. The capacitor 24 is charged and discharged by the driving state (backward or regenerating) of the assist power generation motor 23 and the turning electric motor 25.

The controller 80 generates control commands for the control valve 42 and the power control unit 55 by using the turning operation command signal, the pressure signal, the rotational speed signal, and the like (described later), and the hydraulic sole turning mode. The control of the hydraulic electric hybrid swing mode is switched, the swing control of each mode, the abnormality monitoring of the electric system, and the energy management are performed.

The system configuration and control block diagram of the hydraulic excavator is shown in FIG. Although the system configuration of the electric-hydraulic apparatus shown in FIG. 3 is basically the same as that of FIG. 2, the device, control means, control signal, etc. which are necessary also for performing turning control by this invention are shown in detail.

The hydraulic excavator uses an ignition key 70 for starting the engine 22 and a gate lock lever device 71 in which the pilot pressure shut-off valve 76 is turned ON when the operation is stopped to disable the hydraulic system. Equipped. In addition, the hydraulic excavator is the controller 80 mentioned above, the hydraulic-electric converters 74a, 74bL, 74bR related to the input / output of the controller 80, and the electrical-hydraulic converters 75a, 75b, 75c, 75d. And a hydraulic single swing mode fixed switch 77, which constitutes a swing control system. Hydraulic-electric converter 74a, 74bL, 74bR is a pressure sensor, for example, and electrical-hydraulic converters 75a, 75b, 75c, 75d are electromagnetic proportional pressure reducing valves, for example.

The controller 80 includes the abnormality monitoring / abnormal processing control block 81, the energy management control block 82, the hydraulic-electric combined swing control block 83, the hydraulic single swing control block 84, and the control switching block 85. And so on.

In the state where there is no abnormality in a bond system and the turning electric motor 25 can be driven, the controller 80 selects a hydraulic electric combined turning mode. At this time, the control switching block 85 selects the hydraulic-electric hybrid swing control block 83, and the swing actuator operation is controlled by the hydraulic-electric hybrid swing control block 83. The hydraulic pilot signal generated by the input of the swing operation lever device 72 is converted into an electrical signal by the hydraulic / electric converter 74a, and is input to the hydraulic-electric combined swing control block 83. The operating pressure of the swing hydraulic motor 27 is converted into an electric signal by the hydraulic / electric converters 74bL and 74bR, and is input to the hydraulic-electric combined swing control block 83. The swing motor speed signal output from the inverter for driving the electric motor in the power control unit 55 is also input to the hydraulic-electric combined swing control block 83. The hydraulic-electric hybrid swing control block 83 performs swing operation based on the hydraulic pilot signal from the swing operation lever device 72, the operating pressure signal of the swing hydraulic motor 27, and the swing motor speed signal. The command torque of the motor 25 is calculated, and the torque command EA is output to the power control unit 55. At the same time, torque reduction commands EB and EC for reducing the output torque of the hydraulic pump 41 and the output torque of the hydraulic motor 27 by the torque output by the electric motor 25 are supplied to the electric / hydraulic converters 75a,. 75b).

On the other hand, the hydraulic pilot signal generated by the input of the turning operation lever device 72 is also input to the control valve 42, so that the spool 61 (refer to FIG. 4) for the turning motor is switched from the neutral position and the hydraulic pump ( The discharge oil of 41 is supplied to the turning hydraulic motor 27, and the hydraulic motor 27 is also driven simultaneously.

The amount of power storage of the capacitor 24 is increased or decreased by the difference between the energy consumed during acceleration and the energy regenerated during deceleration. It is the energy management control block 82 which controls this, and the control which maintains the electrical storage quantity of the capacitor 24 by giving electric power generation or an assist command ED to the assist generation motor 23 is performed in a predetermined range.

Abnormality monitoring when a failure, an abnormality, or a warning state occurs in an electric system such as the electric motor 25, the capacitor 24, the power control unit 55, or when the amount of storage of the capacitor 24 is outside the predetermined range. The abnormality processing control block 81 and the energy management control block 82 switch the control switching block 85 to select the hydraulic single swing control block 84, and then from the hydraulic-electric combined swing mode to the hydraulic single swing mode. Switch over. Since the swing hydraulic system is basically matched to operate in cooperation with the electric motor 25, the hydraulic single swing control block 84 receives the swing drive characteristic correction command EE and the swing pilot pressure correction command EF. By outputting to the electric-hydraulic converter 75c, 75d, respectively, the correction which increases the drive torque of the hydraulic motor 27 and the correction which increases the braking torque of the hydraulic motor 27 are performed, Control is performed so that turning operability is not impaired even without torque.

The hydraulic single swing mode fixed switch 77 is used when it is desired to be fixed in the hydraulic single swing mode for some reason, such as a failure of the electric system or a specific attachment, and the fixed switch 77 is turned to the ON position. When operated, the switching control block 85 is fixed to select the hydraulic sole swing control block 84.

The details of the swing hydraulic system are shown in FIG. The same code | symbol is attached | subjected to the element similar to FIG. The control valve 42 of FIG. 3 is provided with a valve component called a spool for every actuator, and the opening area is changed by displacing the corresponding spool according to the instruction (hydraulic pilot signal) from the operation lever device 72, 73, The flow rate of the pressurized oil which passes through the flow path of each spool changes. The swing hydraulic system shown in FIG. 4 extracts the circuit part including only the swing spool.

The swing hydraulic system includes a first mode in which the maximum output torque of the swing hydraulic motor 27 becomes the first torque, and a second torque in which the maximum output torque of the swing hydraulic motor 27 becomes larger than the first torque. Can be changed to 2 modes. The details will be described below.

In Fig. 4, the swing hydraulic system includes the hydraulic pump 41 and the swing hydraulic motor 27, the swing spool 61, the variable overload relief valves 62a and 62b for swing, The center bypass cut valve 63 as a turning auxiliary valve is provided.

The hydraulic pump 41 is a variable displacement pump, has a regulator 64 having a torque control unit 64a, and the tilting angle of the hydraulic pump 41 is changed by operating the regulator 64 so that the hydraulic pump 41 The capacity changes, and the discharge flow rate and output torque of the hydraulic pump 41 change. When the torque reduction command EB is output from the hydraulic-electric combined swing control block 83 of FIG. 3 to the electric-hydraulic converter 75a, the electric-hydraulic converter 75a sets the corresponding control pressure to the regulator 61. Output to the torque control unit 64a, and the torque control unit 64a changes the setting of the torque control unit 64a so that the maximum output torque of the hydraulic pump 41 decreases by the torque output from the electric motor 25. .

The torque control characteristic of the hydraulic pump 41 is shown in FIG. The horizontal axis shows the discharge pressure of the hydraulic pump 41, and the vertical axis shows the capacity of the hydraulic pump 41. The characteristics of the solid lines PT and PTS show the maximum torque that the hydraulic pump 41 can output.

When the hydraulic-electric combined swing mode is selected and the torque reduction command EB is output to the electric-hydraulic converter 75a, the electric-hydraulic converter 75a generates a control pressure, and at this time, the control unit 64a The setting of is in the characteristic of the solid line PT by which the maximum output torque decreased rather than the solid line PTS (1st mode). When the hydraulic single swing mode is selected and the torque reduction command EB is not output to the electric / hydraulic converter 75a, the setting of the torque control unit 64a is changed to the characteristic of the solid line PTS (second). Mode), the maximum output torque of the hydraulic pump 41 increases by the area shown by the diagonal lines.

Returning to Fig. 4, the swing spool 61 has three positions A, B, and C, and receives the swing operation command (hydraulic pilot signal) from the operation lever device 72 to the A position or from the neutral position B. Changes to the C position continuously.

The operation lever device 72 incorporates a pressure reducing valve for reducing the pressure from the pilot hydraulic pressure source 29 in accordance with the lever operation amount, and the pressure (hydraulic pilot signal) corresponding to the lever operation amount is one of the left and right of the spool 61 for turning. To the pressure chamber.

When the turning spool 61 is in the neutral position B, the pressurized oil discharged from the hydraulic pump 41 passes through the bleed-off stop and passes through the center bypass cut valve 63 to return to the tank. When the turning spool 61 receives the pressure (hydraulic pilot signal) according to the lever operation amount and changes to the A position, the hydraulic oil from the hydraulic pump 41 passes through the iris, which is a meter at the A position, to allow the turning hydraulic motor 27 to rotate. It is sent to the right side, the return oil from the turning hydraulic motor 27 passes through the meter-out aperture at the A position, and is returned to the tank, and the turning hydraulic motor 27 rotates in one direction. On the contrary, when the turning spool 61 receives the pressure (hydraulic pilot signal) according to the lever operation amount and changes to the C position, the hydraulic oil from the hydraulic pump 41 passes through the iris, which is a meter at the C position, to rotate the hydraulic motor 27. ), The return oil from the turning hydraulic motor 27 passes through the meter-out aperture at the C position and returns to the tank, and the turning hydraulic motor 27 rotates in the reverse direction to the case of the A position. do.

When the swinging spool 61 is located in the middle of the B position and the A position, the hydraulic oil from the hydraulic pump 41 is distributed to the bleed-off aperture and the meter-in aperture. At this time, a pressure corresponding to the opening area of the bleed-off stop and the opening area of the center bypass cut valve 63 is generated at the inlet side of the meter-in stop, and the pressure oil is supplied to the turning hydraulic motor 27 at that pressure. The operating torque is given according to (opening area of the bleed off iris). In addition, the discharge oil from the turning hydraulic motor 27 receives resistance according to the opening area of the meter-out stop at that time, and back pressure is generated, and a braking torque according to the opening area of the meter-out stop is generated. The same applies to the middle of the B position and the C position.

When the operating lever of the operating lever device 72 is returned to the neutral position and the swinging spool 61 is returned to the neutral position B, since the upper swing body 20 is an inertial body, the swing hydraulic motor ( 27) tries to continue the rotation with that inertia. At this time, when the pressure (back pressure) of the discharge oil from the turning hydraulic motor 27 is going to exceed the set pressure of the variable overload relief valve 62a or 62b for turning, the overload relief valve 62a or 62b is carried out. Is operated to withdraw a portion of the pressurized oil to the tank to limit the rise of the back pressure and generate a braking torque according to the set pressure of the overload relief valve 62a or 62b.

FIG. 6: A is a figure which shows the meter in opening area characteristic and the bleed-off opening area characteristic of the turning spool 61 in one Embodiment of this invention, and FIG. 6B is a figure which shows the meter out opening area characteristic. to be.

In FIG. 6A, the solid line MI is an opening area characteristic of meters, and the solid line MB is a bleed-off opening area characteristic, all of which are present embodiments. The dashed-dotted line MB0 is a bleed-off opening area characteristic which can ensure good operability in the conventional hydraulic excavator which does not use an electric motor. The bleed-off opening area characteristic MB of the present embodiment is designed so that the control region start point and the end point are the same as those of the conventional one, but are freely opened (to have a large opening area) in the middle region as compared with the conventional one.

6B, the solid line MO is the meter out opening area characteristic of this embodiment, and the two-dot chain line MO0 does not use an electric motor, and the meter out which can ensure favorable operability in the conventional hydraulic shovel. Opening area characteristic. The meter-out opening area characteristic MO of this embodiment is designed so that a control area start point and an end point may be the same as the conventional one, but open freely (it becomes a large opening area) compared with the conventional one in a middle area.

FIG. 7: is a figure which shows the combined opening area characteristic of the meter-in aperture of the turning spool 61 and the center bypass cut valve 63 with respect to a hydraulic pilot signal (operation pilot pressure).

Since the swing drive characteristic correction command EE is not output when the hydraulic-electric hybrid swing mode is selected, the center bypass cut valve 63 is in the open position of the city, and the meter in of the swing spool 61 is measured. The combined opening area characteristic of the diaphragm and the center bypass cut valve 63 becomes a characteristic of the dotted line MBC determined only by the bleed-off opening area characteristic MB of FIG. 6A (first mode).

When the hydraulic single swing mode is selected, the swing drive characteristic correction command EE is output to the electric-hydraulic converter 75c as described above, and the electric-hydraulic converter 75c centers the corresponding control pressure. It outputs to the hydraulic pressure part of the pass cut valve 63, and the center bypass cut valve 63 is switched to the narrow position of the figure right side. By switching the center bypass cut valve 63, the combined aperture area characteristics of the meter-in aperture of the swing spool 61 and the center bypass cut valve 63 with respect to the hydraulic pilot signal of the swing spool 61 are changed. Is changed to the characteristic of the solid line MBS having a smaller synthetic aperture area than the characteristic of the dotted line MBC (second mode). The composite opening area characteristic of this solid line MBS is equivalent to the bleed-off opening area characteristic MB0 shown in FIG. 6A which can ensure favorable operability in the conventional hydraulic excavator.

8 shows hydraulic pilot signals (pilot pressure), meter-in pressure (M / I pressure), assist torque of the swing electric motor 25, and the upper swing structure 20 at the time of swing driving in the hydraulic-electric hybrid swing mode. It is a figure which shows the time-series waveform of the rotational speed (rotational speed). This is an example of the case where the hydraulic pilot signal is increased in the ramp shape from the pilot pressure 0 and the turning stop state to the pilot pressure maximum at the time T = T1 to T4.

When the hydraulic-electric combined swing mode is selected, the composite aperture area characteristics of the meter-in aperture and center bypass cut valve 63 of the swing spool 61 are shown in FIG. Since it becomes a characteristic determined only by the bleed-off opening area characteristic MB of, since the opening area of a bleed-off aperture is larger than before, the pressure M / I which is a meter in this embodiment becomes low. Since the meter in pressure corresponds to the operating torque (acceleration torque) of the swing hydraulic motor 27, it is necessary to apply the acceleration torque by the electric motor 25 only as long as the meter in pressure is lowered. In FIG. 8, the assist torque on the reverse side is called positive. In the present embodiment, the total value of the assist torque of the electric motor 25 and the acceleration torque derived from the meter-in pressure generated by the swinging spool 61 is almost equal to the acceleration torque generated by the conventional hydraulic excavator. Control to lose. As a result, the turning speed of the upper swinging body 20 can have acceleration wheeling equivalent to that of the conventional hydraulic excavator.

On the other hand, when the hydraulic single swing mode is selected, the composite aperture area characteristics of the meter-in aperture of the swing spool 61 and the center bypass cut valve 63 are smaller than the dotted line MBC of FIG. 7. Since it is changed to the characteristic of the solid line MBS, the meter in pressure generated by the swing spool 61 rises to the meter in pressure of the solid line obtained by the conventional hydraulic excavator shown in FIG. 8, and the swing spool ( The acceleration torque resulting from the meter-in pressure generated by 61) is controlled to be substantially equal to the acceleration torque generated in the conventional hydraulic excavator. As a result, the turning speed of the upper swinging body 20 can have acceleration wheeling equivalent to that of the conventional hydraulic excavator.

In addition, what can be rotated by the hydraulic motor 27 alone is that the maximum output torque of the turning hydraulic motor 27 is larger than the maximum output torque of the turning electric motor 25. This means that in the hydraulic-electric combined swing mode, even if the electric motor 25 makes an unintentional movement, if the hydraulic circuit is normal, the dangerous movement is not so dangerous, and the present invention is also advantageous in terms of safety.

9 is a diagram showing the meter out opening area characteristic of the swinging spool 61 with respect to the hydraulic pilot signal (operation pilot pressure).

Since the hydraulic pilot pressure correction command EF is not output when the hydraulic-electric combined swing mode is selected, the meter out opening area characteristic of the swing spool 61 is determined by the meter out opening area characteristic MO of FIG. 6B. It becomes the characteristic of the dotted line MOC which shows the same change (1st mode).

When the hydraulic single swing mode is selected, the swing pilot pressure correction command EF is output as described above with the electric / hydraulic converter 75d of FIG. 3 (the electro-hydraulic converters 75dL and 75dR of FIG. 4). , The hydraulic-hydraulic converter 75d decompresses and corrects the hydraulic pilot signal (operation pilot pressure) generated by the operation lever device 72. Due to the correction of the hydraulic pilot signal, the meter-out opening area characteristic of the hydraulic pilot signal of the swinging spool 61 is a solid line in which the opening area in the intermediate region is reduced with respect to the characteristic of the dotted line MOC of FIG. MOS) characteristic (second mode). The opening area characteristic of this solid line MOS is equivalent to the meter out opening area characteristic MO0 shown in FIG. 6B which can ensure favorable operability in the conventional hydraulic excavator.

10 shows hydraulic pilot signals (pilot pressure), meter out pressure (M / O pressure), assist torque of the swing electric motor 25, and upper swing structure (at the time of turning braking stop in the hydraulic-electric hybrid swing mode). It is a figure which shows the time-series waveform of the rotational speed (rotational speed) of 20). This is an example of the case where the hydraulic pilot signal is reduced in the ramp shape from the pilot pressure maximum and the maximum turning speed to the pilot pressure 0 at the time T = T5 to T9.

When the hydraulic electric hybrid swing mode is selected, the meter out opening area characteristic of the hydraulic pilot signal of the swing spool 61 as shown by the dotted line (MOC) in FIG. As shown in FIG. 6B, the meter-out pressure (M / O pressure) is lower in the present embodiment because the opening area of the meter-out aperture is larger than in the prior art as shown in FIG. 6B. Since the meter out pressure corresponds to the brake torque (braking torque), it is necessary to apply the brake torque by the electric motor 25 only as long as the meter out pressure is lowered. In FIG. 10, the assist torque on the regenerative side is called negative. In this embodiment, the total value of the assist torque of the electric motor 25 and the brake torque resulting from the meter-out pressure generated by the swinging spool 61 is made to be almost equal to the brake torque generated by the conventional hydraulic excavator. To control. As a result, the turning speed of the upper swinging body 20 can have a deceleration wheeling equivalent to a conventional hydraulic excavator.

On the other hand, when the hydraulic single swing mode is selected, the meter-out opening area characteristic of the hydraulic pilot signal of the swinging spool 61 decreases in the opening area in the intermediate region with respect to the characteristic of the dotted line (MOC) in FIG. Since it is changed to the characteristic of the solid line MOS, the meter out pressure generated by the turning spool 61 rises to the meter out pressure of the solid line obtained by the conventional hydraulic excavator shown in FIG. The brake torque resulting from the meter-out pressure generated by 61) is controlled to be approximately equal to the brake torque generated by the conventional hydraulic excavator, and the turning speed of the upper swinging body 20 is equal to that of the conventional hydraulic excavator. It becomes possible to have equivalent deceleration wheeling.

FIG. 11: is a figure which shows the relief pressure characteristic of the variable overload relief valve 62a, 62b for turning.

When the hydraulic-electric combined swing mode is selected and the torque reduction command EC is output from the electric / hydraulic converter 75b of FIG. 3 (total / hydraulic converters 75bL and 75bR of FIG. 4), The hydraulic converter 75b generates a control pressure, and the control pressure acts on the set pressure reducing side of the variable overload relief valves 62a and 62b, and the relief characteristics of the variable overload relief valves 62a and 62b are The relief pressure is a characteristic of the solid line SR having Pmax1 (first mode). When the hydraulic single turning mode is selected and the torque reduction command EC is not output from the electric / hydraulic converter 75b (the electric / hydraulic converters 75bL and 75bR in Fig. 4), the electric / hydraulic converter Since 75b does not generate the control pressure, the relief characteristics of the variable overload relief valves 62a and 62b become the characteristics of the solid line SRS in which the relief pressure rises from Pmax1 to Pmax2 (second mode), and braking. The torque increases as the relief pressure increases.

When the hydraulic-electric combined swing mode is selected by this, since the relief pressure of the variable overload relief valves 62a and 62b is set to Pmax1 lower than Pmax2, the operation lever of the operation lever device 72 was returned to the neutral position. At that time, the pressure (back pressure) of the discharge oil from the turning hydraulic motor 27 rises to Pmax1 which is a slightly lower set pressure of the variable overload relief valves 62a and 62b, and the assist torque of the electric motor 25 is variable. The total value of the brake torque resulting from the back pressure generated by the overload relief valve 62a or 62b is controlled to be approximately equal to the brake torque generated in the conventional hydraulic excavator, and the turning speed of the upper swing body 20 is controlled. It becomes possible to have a deceleration wheeling equivalent to a conventional hydraulic excavator.

In addition, when the hydraulic single swing mode is selected, since the relief pressures of the variable overload relief valves 62a and 62b are set to Pmax2 higher than Pmax1, when the operation lever of the operation lever device 72 is returned to the neutral position. Then, the pressure (back pressure) of the discharge oil from the turning hydraulic motor 27 rises to Pmax2, which is the higher set pressure of the variable overload relief valves 62a, 62b, and the variable overload relief valve 62a or 62b. The brake torque derived from the back pressure generated by) is controlled to be substantially equal to the brake torque generated by the conventional hydraulic excavator, and the turning speed of the upper swing body 20 is reduced to the same as that of the conventional hydraulic excavator. It becomes possible to have wheeling.

12 shows a sequence of switching from the hydraulic-electric combined swing mode to the hydraulic single swing mode by the abnormality monitoring / abnormal processing control block 81 of the controller 80.

The abnormality monitoring / abnormal processing control block 81 is a signal (notice) when a failure, an abnormality, or a warning state occurs in an electric system such as the electric motor 25, the capacitor 24, or the power control unit 55. It is determined whether or not an error signal has been notified from the power control unit 55 (step S100), and if an error signal is notified, it is further determined whether it is an error signal requiring emergency response (step S110). . At the time of mode switching, there is a possibility that a light shock may occur due to the valve switching operation of the hydraulic system, and if the content of the error signal is not serious and there is no urgency to switch immediately, it is determined whether or not the timing can be switched. (Step S120), the timing of the operation of the swinging body 20 and the input of the swing lever 72 for turning, or the operation of the traveling, front, and their operation levers which are devices other than the swinging body 20. The input of the device 73 is also included, and switching is performed at the time of idling or the like in which the operation is not completely performed (step S130). An abnormality that may damage the system, such as an overcurrent abnormality of the inverter, or that may lead to a serious failure or disaster, may stop the electric system immediately even during operation to switch to the hydraulic single swing mode (steps S110 to S130).

FIG. 13 shows a return sequence from the hydraulic single swing mode to the hydraulic-electric combined swing mode by the abnormality monitoring / abnormal processing control block 81 of the controller 80.

When the abnormality monitoring / abnormal processing control block 81 switches to the hydraulic single swing mode by the processing shown in the flowchart of FIG. 12, first, a predetermined error signal canceling process is performed during hydraulic single swing control (step S150). . In the error signal canceling process, when the occurrence of an error signal is caused by, for example, an overvoltage state or an overtemperature state, processing such as waiting until the state is canceled is performed. Subsequently, it is determined whether or not the error signal has been canceled (step S160). If the error signal has been canceled by the error signal canceling process or naturally, it is further determined whether or not the timing can be switched mode (step S170). Switching (return operation) to the hydraulic-electric combined swing mode is performed at the timing of the operation and the operation not being performed, or at the time of the idling including the front and the operation is not performed completely (step S180).

The hydraulic excavator having two switchable swing modes according to the present invention is particularly effective at the start of the machine. The starting sequence of a normal (having only hydraulic swing motor) hydraulic excavator is shown in FIG. When the ignition key is set to the start position from the on position, the engine and the hydraulic pump are started, and the gate lock lever is released to immediately operate the all-hydraulic actuator including the swing.

Fig. 15 shows a start sequence of a conventional hybrid hydraulic excavator using an electric motor and a hydraulic motor for swing driving, and a capacitor for the power storage device. In the figure, the dotted line is the processing of the controller. In the conventional hybrid hydraulic excavator, even when the engine and the hydraulic pump are started, if the capacitor does not have a sufficient amount of power storage, the turning operation cannot be performed immediately. The capacitor has a small capacity, and if the machine is not operated for several days, there is a possibility that it is impossible to secure the amount of power storage required for turning drive by natural discharge. Therefore, at the time of machine start-up, initial charging is first required (steps S200 to S240), and the operator needs to wait until the charging is completed.

The starting sequence of the hybrid hydraulic excavator of the present invention is shown in FIG. In the figure, the dotted line is the process of the energy management control part 82 of the controller 80. As shown in FIG. In the hybrid hydraulic excavator of the present invention, in any state of electrical, the energy management control unit 82 sets the hydraulic single swing control block 84 as the initial setting to set the hydraulic single swing mode (step S300). As a result, the operator operates the gate lock lever device 71 from the locked position to the unlocked position to turn off the pilot pressure shutoff valve 76, whereby the hydraulic excavator becomes operable immediately. While the operator operates the hydraulic excavator and performs work, the energy management control unit 82 performs charging, discharging control, etc. in the background (steps S310 to S350), and after the turning electric motor becomes driven, the mode It is confirmed that it is a switchable timing (step S360), and it switches to the hydraulic-electric combined swing mode (step S370).

Charge and discharge control by the energy management control unit 82 is performed as follows. First, the power control unit 55 is started (step S310), and the initial charging process of the inverters 52, 53 and the smoothing capacitor 54 and the connection process of the main contactor 56 are performed (step S320). Subsequently, it is determined whether or not the capacitor 24 is at the specified voltage (step S330). If the capacitor 34 is less than or equal to the specified voltage, a generation command is output to the assist generation motor 23 to perform capacitor charge control. If abnormal, the chopper 51 is controlled to perform capacitor discharge control through a grid resistor (not shown) (step S340). When the capacitor 24 reaches the specified voltage, the preparation state of the hydraulic-electric combined swing mode is set (step S350).

As described above, according to the present embodiment, both the hydraulic motor 27 and the electric motor 25 are provided for driving the swinging structure 20, and both the torques of the hydraulic motor 27 and the electric motor 25 are provided. In the hydraulic-electric combined swing mode, for example, pressing is performed by setting the switchable mode (hydraulic electric combined swing mode) and the hydraulic motor 27 to swing mode alone (hydraulic independent swing mode). Energy saving can be realized by realizing the operation operation peculiar to hydraulic actuators such as excavation and the like, and the operation feeling peculiar to hydraulic actuators, and regenerating the kinetic energy of the swinging body 20 by the electric motor 25 during braking (deceleration). It can be realized. In addition, when the remaining energy amount of the capacitor 24 is insufficient to store the regenerated electric energy, in the case of overcharge, or in the case of failure, abnormality, or warning in the electric system, by switching to the hydraulic single swing mode. By the hydraulic motor 27 alone, it can drive with normal turning torque, and can continue working as a hydraulic excavator. In addition, at the time of start-up, even if the energy remaining amount of the capacitor 24 is insufficient, it becomes possible to start work immediately.

FIG. 17 shows a system configuration of main electric / hydraulic devices of the hybrid hydraulic excavator according to the second embodiment of the present invention. In the first embodiment shown in FIG. 2, the assist power generation motor 23 connected to the drive shaft of the engine 22 is used. In the present embodiment, instead of the configuration, the discharge oil of the hydraulic pump 41 is used. The driven hydraulic motor 101 and the electric motor 100 (charging device) which has a power generation function connected to the drive shaft of this hydraulic motor 101 are used. As the power storage device, all power storage devices such as a lithium ion capacitor, a lithium ion battery, a nickel hydride battery, and the like, in addition to the electric double layer capacitor 24 can be used. In the embodiment shown in FIG. 17, a battery such as a lithium ion battery (103) is used.

The system structure of the main electric and hydraulic equipment of the hybrid hydraulic excavator which concerns on FIG. 18 at 3rd Embodiment of this invention is shown. In this embodiment, in order to perform initial charge of the capacitor 24, the structure which boosts by using the DC / DC converter 112 from the electric field battery line containing the alternator 110 and the electric field battery 111 is used. I did it. In this case, however, when surplus energy is generated in the capacitor 24, energy cannot be freely released to the electric field battery line, so that the energy management control unit 82 maintains a certain amount of capacitor storage by only the acceleration and deceleration of the turning operation. Control is required.

19 and 20 show the system configuration of main electric / hydraulic equipment of the hybrid hydraulic excavator according to the fourth and fifth embodiments of the present invention.

Although the hydraulic excavator which used the engine 22 as a prime mover was shown in the previous embodiment, there is no problem even if this invention is applied to the hydraulic excavator which used another prime mover, for example, an electric motor. In the embodiment shown in FIG. 19, the hydraulic excavator using the electric motor 120 driven by the AC power from the commercial AC power supply 121, and the embodiment shown in FIG. 20, the electric drive driven by the large capacity battery 130 The system block diagram of the hydraulic excavator using the motor 120 is shown. In the embodiment shown in FIG. 19, similarly to the embodiment of FIG. 18, in order to perform initial charge of the capacitor 24, the voltage is boosted using the DC / DC converter 122 from the commercial AC power supply 121.

When applying the present invention to the hydraulic excavator using the electric motor 120 as the prime mover, it should be noted that if a power line or a power control unit is shared between the turning electric motor and the prime mover electric motor, these failures may occur. In the case, there is a possibility that even the operation in the hydraulic alone swing mode may be disabled.

In the embodiment shown in FIG. 19, the main electric motor 120 is a three-phase alternating current induction motor, which is directly driven by three-phase alternating current of the commercial power supply 121, and uses the energy stored in the capacitor 24. It is set as the power supply line separate from the electric motor 25 for power. In the embodiment shown in FIG. 20, when the power control units 132 and 133 are separated from the main circuit and the turning circuit, and abnormality such as a short circuit failure occurs in the turning electric motor 25 or the turning power control unit 133, By separating by the turning transmission part disconnect relay 134, operation in the hydraulic single turning mode is comprised possible.

As mentioned above, although embodiment when the present invention was applied to the hydraulic excavator was described, the gist of this invention makes it possible to switch between a hydraulic-electric hybrid turning mode and a hydraulic single turning mode with respect to the drive of a turning body. The present invention is applicable to construction machinery having a swing structure other than a hydraulic excavator in general.

10... Lower traveling body
11 ... Crawler
12... Crawler frame
13 ... Space-Pressing Oil Motor
14 ... Left driving hydraulic oil motor
20... Upper pivot
21 ... Turning frame
22... engine
23 ... Assist generation motor (charger)
24 ... Capacitor
25... Slewing electric motor
26 ... Deceleration mechanism
27 ... Slewing hydraulic motor
30 ... Shovel Mechanism (Front Device)
31 ... Boom
32 ... Boom cylinder
33 ... Arm
34 ... Arm cylinder
35 ... bucket
36 ... Bucket cylinder
40 ... Hydraulic system
41 ... Hydraulic pump
42 ... Control valve
43 ... Hydraulic piping
51 ... chopper
52 ... Inverter for swing electric motor
53 ... Inverter for assist generating motor
54 ... Smoothing capacitor
55 ... Power control unit
56 ... Main contactor
57... Main relay
58... Inrush Current Protection Circuit
61... Swing spool
62a, 62b... Variable Overload Relief Valve
63 ... Center Bypass Cut Valve
64 ... regulator
64a... Torque control unit
70 ... Ignition key
71 ... Gate lock lever
72 ... Swing lever device
73 ... Operation lever device (other than turning)
74a, 74bL, 74bR... Hydraulic and electric converter
75a, 75b, 75c, 75d... Electric, hydraulic converter
76 ... Pilot Pressure Signal Shutoff Valve
77... Hydraulic sole swing mode fixed switch
80 ... Controller (control device)
81 ... Error monitoring and error processing control block
82 ... Energy Management Control Block
83 ... Hydraulic Electric Composite Slewing Control Block
84 ... Hydraulic sole control block
85 ... Control switching block
100... Electric motor (charger)
101 ... Hydraulic motor
103 ... battery
110 ... Alternator
111... Electric Field Battery
112 ... DC / DC converter
120 ... Main electric motor
121 ... Commercial power
122 ... AC / DC Converter
130 ... Large capacity battery
131 ... Power control unit
132 ... Power control unit for main electric motor
133 ... Power Control Unit for Slewing Electric Motors
134 ... Slewing electric drive disconnect relay

Claims (15)

Prime mover 22,
A hydraulic pump 41 driven by the prime mover,
Revolving body 20,
The electric motor 25 for driving the swing structure,
A hydraulic motor 27 for driving the swing structure driven by the hydraulic pump;
A power storage device 24 connected to the electric motor,
An operating lever device 72 for turning instructing the driving of the swinging body;
A hydraulic-electric combined swing mode in which both the electric motor and the hydraulic motor are driven when the operating lever device for swing is operated, and the swing body is driven by a total of torques of the electric motor and the hydraulic motor; And a control device 80 for driving only the hydraulic motor when the operating lever device for swing is operated, and for switching the hydraulic single swing mode for driving the swing body with the torque of the hydraulic motor alone. Hybrid construction machine. The method of claim 1,
The control device 80 drives the swinging body 20 in the hydraulic-electric combined swing mode in the normal operation state, and drives the electric motor including the electric motor 25 and the power storage device 24. The hybrid construction machine, which automatically switches from the hydraulic-electric combined swing mode to the hydraulic single swing mode when a failure, abnormality, or warning condition occurs in the transmission system for driving. The method of claim 2,
The control device (80) is a hybrid construction machine, characterized in that automatically switching from the hydraulic single swing mode to the hydraulic electric combined swing mode when the failure, abnormality, and warning are resolved. The method of claim 1,
When the electrical storage amount of the said electrical storage device 24 exists in the predetermined range, the said control apparatus 80 drives the said turning body 20 in the said hydraulic-electric hybrid turning mode, and the electrical storage amount of the said electrical storage device became out of a predetermined range. And, at the time of automatically switching from the hydraulic-electric combined swing mode to the hydraulic single swing mode. 5. The method according to any one of claims 1 to 4,
The said control apparatus (80) performs switching of the said hydraulic-electric combined swing mode and the said hydraulic single swing mode only in the state which the operation | movement of the said turning body (20) is not performed, The hybrid construction machine characterized by the above-mentioned. 5. The method according to any one of claims 1 to 4,
The control device 80 is a state in which the operation of the swinging body 20 and the operation lever device 72 for swinging are not performed to switch between the hydraulic-electric hybrid swinging mode and the hydraulic single swinging mode. Hybrid construction machine, characterized in that limited to. 5. The method according to any one of claims 1 to 4,
The control device 80 switches between the composite swing mode and the single swing mode by inputting the operation of the swing body 20 and the operation lever device 72 for swing, and the swing body ( A hybrid construction machine, characterized in that the operation is performed only in a state in which neither the operations of 10 and 30 and the input of the operating device 73 for devices other than the swing structure are performed. 5. The method according to any one of claims 1 to 4,
The hydraulic motor 27 is capable of outputting the maximum torque capable of driving the swinging body 20 alone, the maximum torque of the electric motor 25 is lower than the maximum torque of the hydraulic motor hybrid Construction machinery. The method of claim 1,
The control device 80 is a charging device 23 when the power storage amount of the power storage device 24 is immediately lower than a predetermined power storage amount required to operate in the hydraulic-electric combined swing mode immediately after the start of the construction machine. When the operation lever device 72 for the swing is operated during the charging process while charging to the power storage device, the swing operation in the hydraulic single swing mode is performed, and the power storage device performs a predetermined power storage. After reaching a quantity, the hybrid construction machine, characterized by switching to the hydraulic-electric hybrid swing mode. The method of claim 1,
The control device 80, when the power storage amount of the power storage device 24 immediately after the start of the construction machine is higher than a predetermined power storage amount required to operate in the hydraulic-electric combined swing mode, from the power storage device When the operation lever device 72 for the swing is operated during the discharge process while the discharge is performed, the swing operation in the hydraulic single swing mode is performed, and after the power storage device reaches a predetermined power storage amount, Hybrid construction machine, characterized in that for switching to the hydraulic electric combined swing mode. 11. The method according to any one of claims 1 to 10,
The prime mover is an electric motor (120), the power source is a hybrid construction machine, characterized in that the commercial AC power source (121). 11. The method according to any one of claims 1 to 10,
The prime mover is an electric motor (120), the power supply is the power storage device (130), the hybrid construction machine. The method of claim 1,
A power control unit 55 for controlling the transfer of electric power between the power storage device 24 and the electric motor 25;
And a swing hydraulic system including a swing spool 61 for controlling the flow of the pressurized oil supplied from the hydraulic pump 41 to the hydraulic motor 27 and the flow of the pressurized oil returned from the hydraulic motor to the tank. ,
The swing hydraulic system is changeable to a first mode in which the maximum output torque of the hydraulic motor is a first torque, and in a second mode in which the maximum output torque of the hydraulic motor is a second torque greater than the first torque, ,
The control device 80 switches the swing hydraulic system to the first mode, and outputs a torque command to the power control unit 55 when the swing lever device 72 is operated to output the torque motor. And a hydraulic electric swing control unit 83 for driving the hydraulic swing control unit 83 for switching the swing hydraulic system to the second mode and stopping the output of the torque command to the power control unit 55. A hybrid construction machine, characterized by switching between the hydraulic-electric combined swing mode and the hydraulic single-turn mode by selecting one of the hydraulic-electric combined swing control unit and the hydraulic single-turn control unit. The method of claim 13,
The control device 80 selects the hydraulic-electric combined swing control unit 83 in a normal operation state, and includes an electric motor 25, the power storage device 24, and the power control unit 55. And an abnormality monitoring control section (81) for selecting the hydraulic single swing control section (84) when any failure, abnormality, or warning condition occurs. The method of claim 13,
The control device 80 selects the hydraulic-electric combined swing control unit 83 when the power storage amount of the power storage device 24 is within a predetermined range, and when the power storage amount of the power storage device is out of a predetermined range, the hydraulic single swing. The hybrid construction machine further comprises an energy management control part 82 which selects the control part 84.

Images